[Audio Metric] pixelstats: add cca_rate sysfs for VendorAudioHardwareStatsReported on Zuma Test: Local Test Bug: 289166146 Merged-In: I0b476417bd14972681c7ea7fb18ddff2aa8ed4ee Change-Id: Ie5f0ad9825f7a9a5c00fb96088c0cad4647562e4